System and method for controlling a machine

ABSTRACT

A system for controlling a machine includes a first controller, a second controller, and a comparator. During a first cycle, the first controller generates a control signal to the machine while the second controller generates a predicted parameter signal. During the first cycle, the comparator transmits a feedback signal to the second controller if a predetermined threshold is not met. A method for controlling a machine includes transmitting a control signal from a first controller to the machine and generating a predicted parameter value in a second controller. The method further includes transmitting a feedback signal to the second controller if a predetermined threshold is not met.

FIELD OF THE INVENTION

The present invention generally involves a control system for a machine.Specifically, the present invention describes and enables a controllerthat may be used with a machine such as generator or a motor to regulatethe operation of the machine according to desired parameters.

BACKGROUND OF THE INVENTION

Machines such as motors and generators typically include a controlsystem for regulating various parameters in the machine. For example, amotor may include a control system that regulates the torque or speed ofthe motor to prevent the motor from overheating. Similarly, a generatormay include a controller that regulates the current or voltage producedby the generator.

Various circuits and methods are known in the art for controllingmachines. For example, a control system may operate essentiallyaccording to trial and error by issuing a control signal to alter theoperation of the machine and then varying the magnitude of the controlsignal based on the machine's response to the control signal. Forexample, a controller attempting to raise the output voltage of agenerator may issue an initial control signal and then adjust thatinitial control signal depending on the resulting change in the outputvoltage of the generator. While simple in its methodology, this trialand error approach typically requires more time to achieve the desiredoperating level of the machine, and it may result in excessive huntinguntil the machine stabilizes at the desired operating level.

To avoid the disadvantages of trial and error, some control systems mayinclude programming or circuitry that models the operation of themachine. The control system accesses the programming or circuitry togenerate an appropriate control signal that efficiently and preciselyalters the machine operation to produce the desired parameter value. Insome cases, the programming or circuitry may be generic to an entireclass of machines, while in other cases, the programming or circuitrymay be specifically tailored to each type of machine, or, moreparticularly, to an individual machine in a class of machines.

The ability of the control system to accurately and efficiently regulatethe machine is directly dependent on the ability of the programming orcircuitry to accurately model the operation of the particular machine.For example, in the field of wind turbine generators, many differentgenerator designs exist to allow the optimum production of power invarying environmental situations. Many differences (e.g., the length,balance, and pitch of the rotating blades) exist between the variousgenerator designs and even between individual generators in each design.In addition, variables unique to each installation (e.g., wind speed,atmospheric pressure, and humidity) may change over time or betweenseasons to vary the performance of individual generators. Lastly,changes in the generator over the life of the generator (e.g., friction,corrosion, changes in balance) may alter the operating characteristicsof the generator.

Therefore the need exists for an improved control system for machines.Ideally, the improved control system may include a model of themachine's operating characteristics that can be updated or adjusted toreflect the actual performance of the machine over time.

BRIEF DESCRIPTION OF THE INVENTION

Aspects and advantages of the invention are set forth below in thefollowing description, or may be obvious from the description, or may belearned through practice of the invention.

In one embodiment of the present invention, a system for controlling amachine includes an input signal, a first parameter signal, and a firstcontroller. The input signal conveys a desired operating parameter ofthe machine, and the first parameter signal conveys a measured parameterof the machine taken at a first time. During a first cycle, the firstcontroller receives the input signal and the first parameter signal andgenerates a control signal to the machine based on the input signal andthe first parameter signal. The system further includes a secondcontroller, a second parameter signal, a feedback circuit, and acomparator. During the first cycle, the second controller receives thefirst parameter signal and the control signal and generates a predictedparameter signal based on the first parameter signal and the controlsignal. The second parameter signal conveys the measured parameter ofthe machine taken at a second time, and the feedback circuit receivesthe second parameter signal and the predicted parameter signal andgenerates a feedback signal based on the second parameter signal and thepredicted parameter signal. During the first cycle, the comparatorreceives the feedback signal and transmits the feedback signal to thesecond controller if a predetermined threshold is not met.

Another embodiment of the present invention is a system for controllinga machine that includes an input signal, a first parameter signal, acontroller, and a first model. The input signal conveys a desiredoperating parameter of the machine, and the first parameter signalconveys a measured parameter of the machine taken at a first time. Thecontroller receives the input signal and the first parameter signal andgenerates a request signal based on the input signal and the firstparameter signal. During a first cycle, the first model receives therequest signal and generates a response signal based on the requestsignal, and the controller receives the response signal and generates acontrol signal to the machine based on the response signal. The systemfurther includes a second model, a second parameter signal, a feedbackcircuit, and a comparator. During the first cycle, the second modelreceives the first parameter signal and the control signal and generatesa predicted parameter signal based on the first parameter signal and thecontrol signal. The second parameter signal conveys the measuredparameter of the machine taken at a second time, and the feedbackcircuit receives the second parameter signal and the predicted parametersignal and generates a feedback signal based on the second parametersignal and the predicted parameter signal. During the first cycle, thecomparator receives the feedback signal and transmits the feedbacksignal to the second model if a predetermined threshold is not met.

Another embodiment of the present invention includes a method forcontrolling a machine. The method includes measuring a parameter at afirst time to determine a first parameter value and comparing the firstparameter value to a desired value. In a first cycle, the methodincludes transmitting a control signal from a first controller to themachine to vary the first parameter value and measuring the parameter ata second time to determine a second parameter value. In the first cycle,the method further includes generating a predicted parameter value in asecond controller based on the first parameter value and the controlsignal and comparing the predicted parameter value to the secondparameter value. The method also includes generating a feedback signalbased on the predicted parameter value and the second parameter valueand, in the first cycle, transmitting the feedback signal to the secondcontroller if a predetermined threshold is not met.

A still further embodiment of the present invention is a system forcontrolling a machine that includes an input signal, a first parametersignal, a first model, and a controller. The input signal conveys adesired operating parameter of the machine, and the first parametersignal conveys a measured parameter of the machine taken at a firsttime. During a first cycle, the first model receives the input signaland the first parameter signal and generates a response signal based onthe input signal and the first parameter signal. The controller receivesthe response signal and generates a control signal to the machine basedon the response signal. The system further includes a second model, asecond parameter signal, a feedback circuit, and a comparator. Duringthe first cycle, the second model receives the first parameter signaland the control signal and generates a predicted parameter signal basedon the first parameter signal and the control signal. The secondparameter signal conveys the measured parameter of the machine taken ata second time, and the feedback circuit receives the second parametersignal and the predicted parameter signal and generates a feedbacksignal based on the second parameter signal and the predicted parametersignal. During the first cycle, the comparator receives the feedbacksignal and transmits the feedback signal to the second model if apredetermined threshold is not met.

Those of ordinary skill in the art will better appreciate the featuresand aspects of such embodiments, and others, upon review of thespecification.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including thebest mode thereof to one skilled in the art, is set forth moreparticularly in the remainder of the specification, including referenceto the accompanying figures, in which:

FIG. 1 shows a simplified block diagram of a control system according toone embodiment of the present invention;

FIG. 2 shows a simplified block diagram of the control system shown inFIG. 1 after a predetermined threshold is met;

FIG. 3 shows a simplified block diagram of a control system according toa second embodiment of the present invention;

FIG. 4 shows a simplified block diagram of the control system shown inFIG. 3 after a predetermined threshold is met;

FIG. 5 shows a simplified block diagram of a control system according toa third embodiment of the present invention; and

FIG. 6 shows a simplified block diagram of the control system shown inFIG. 5 after a predetermined threshold is met.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to present embodiments of theinvention, one or more examples of which are illustrated in theaccompanying drawings. The detailed description uses numerical andletter designations to refer to features in the drawings. Like orsimilar designations in the drawings and description have been used torefer to like or similar parts of the invention.

Each example is provided by way of explanation of the invention, notlimitation of the invention. In fact, it will be apparent to thoseskilled in the art that modifications and variations can be made in thepresent invention without departing from the scope or spirit thereof.For instance, features illustrated or described as part of oneembodiment may be used on another embodiment to yield a still furtherembodiment. Thus, it is intended that the present invention covers suchmodifications and variations as come within the scope of the appendedclaims and their equivalents.

FIGS. 1 and 2 show a simplified block diagram of a control system 10according to one embodiment of the present invention. FIG. 1 showscommunication lines in the system 10 during a first cycle, and FIG. 2shows the communication lines in the system 10 during a second orsubsequent cycle after a predetermined threshold has been met. The solidlines in each figure represent the active communication lines, while thedashed lines in each figure represent the inactive communication lines.Although this embodiment is illustrated and described in the context ofa wind turbine generator 12, one of ordinary skill in the art wouldunderstand that the concepts, structure, and methods described in thepresent application would be equally applicable to any generator, motor,or other machine.

As shown in FIG. 1, the system 10 includes an input device 14, a firstcontroller 16, and a second controller 18. The input device 14 mayinclude any structure for providing an interface between a user and thesystem 10. For example, the input device 14 may include a keyboard,computer, terminal, tape drive, and/or any other device for receivinginput from a user and providing the input to the system 10. The inputdevice 14 generates an input signal 20 which conveys a desired operatingparameter for the wind turbine generator 12. The operating parameter maybe any measurable parameter generated by the wind turbine generator 12,such as, for example, voltage, current, power, or torque.

The first 16 and second 18 controllers may include various componentssuch as memory/media elements 22 and/or coprocessors 24 that store data,store software instructions, and/or perform subroutines called for bythe respective controller. The various memory/media elements may be oneor more varieties of computer readable media, such as, but not limitedto, any combination of volatile memory (e.g., RAM, DRAM, SRAM, etc.),non-volatile memory (e.g., flash drives, hard drives, magnetic tapes,CD-ROM, DVD-ROM, etc.), and/or other memory devices (e.g., diskettes,magnetic based storage media, optical storage media, etc.). Therespective controllers may access the data and/or software instructionsstored in the associated memory/media elements. Any possible variationsof data storage and processor configurations will be appreciated by oneof ordinary skill in the art.

The system 10 operates on a cyclic basis. During one cycle, the firstcontroller 16 regulates the operation of the wind turbine generator 12,and the second controller 18 receives feedback signals to refine itsability to accurately predict the operation of the wind turbinegenerator 12. When a predetermined threshold is met during the first orsubsequent cycles, the operation of the first 16 and second 18controllers switches so that the second controller 18 regulates the windturbine generator 12 while the first controller 16 receives feedbacksignals.

For example, during the first cycle shown in FIG. 1, the firstcontroller 16 receives the input signal 20 from the input device 14 anda first parameter signal 26 from the wind turbine generator 12. Thefirst parameter signal 26 conveys a measured parameter of the windturbine generator 12, such as voltage or current, taken at a first time.The first controller 16 may access the memory/media element 22 orcoprocessor 24, as previously described, to generate a control signal 28to the wind turbine generator 12 based on the input signal 20 and thefirst parameter signal 26. The control signal 28 conveys information orinstructions to the wind turbine generator 12 to alter the operation ofthe wind turbine generator 12 and thereby change the value of themeasured parameter. For example, the input signal 20 may convey adesired output voltage of 400 volts, and the first parameter signal 26may indicate an output voltage from the wind turbine generator 12 of 398volts. Using the data and/or instructions stored in the memory/mediaelement 22 and/or coprocessor 24, the first controller 16 may generatethe control signal 28 to the wind turbine generator 12 that changes theexcitation field of the wind turbine generator 12 to increase the outputvoltage from 398 volts to 400 volts.

Substantially simultaneously during the first cycle, the secondcontroller 18 receives the first parameter signal 26 from the windturbine generator 12 and the control signal 28 from the first controller16. The second controller 18 may access the memory/media element 22 orcoprocessor 24, as previously described, to generate a predictedparameter signal 30 based on the first parameter signal 26 and thecontrol signal 28. The predicted parameter signal 30 conveys theanticipated response of the wind turbine generator 12 to the controlsignal 28. For example, if the first parameter signal 26 conveyed anoutput voltage of 398 volts, and the control signal 28 increased theexcitation field by 2 millivolts, the second controller 18 may predictthat, in response to the control signal 28, the wind turbine generator12 will produce a new output voltage of 399 volts (i.e., the predictedparameter signal 30).

The system 10 shown in FIGS. 1 and 2 further includes a delay circuit32, a feedback circuit 34, and a comparator 36 to provide feedback tothe first 16 or second 18 controllers. The delay circuit 32, feedbackcircuit 34, and comparator 36 may reside in the first 16 and/or second18 controllers and utilize the processing capability and/or memory/mediaelements available in the first 16 and/or second 18 controllers.Alternatively, the delay circuit 32, feedback circuit 34, and/orcomparator 36 may be implemented by hardwire logic or other circuitry,including, but not limited to application specific circuits.

The delay circuit 32 receives the first parameter signal 26 and indexesthe first parameter signal 26 to the time at which the first parameterwas measured. The delay circuit 32 produces a second parameter signal 38indexed to a second time, and the second parameter signal 38 correspondsto the measured parameter after the wind turbine generator 12 hasreceived and acted on the control signal 28.

The feedback circuit 34 receives the second parameter signal 38 from thedelay circuit 32 and the predicted parameter signal 30 from the secondcontroller 18. The feedback circuit 34 compares the second parametersignal 38 to the predicted parameter signal 30 and generates a feedbacksignal 40. The comparator 36 receives the feedback signal 40 andtransmits the feedback signal 40 to the second controller 16 if apredetermined threshold is not met. The predetermined threshold may be atime interval, an acceptable magnitude for the feedback signal 40, orany other metric that indicates the ability of the second controller 18to accurately predict the wind turbine generator's 12 response to thecontrol signal 28. In this manner, if the predetermined threshold is notmet during the first cycle, the comparator 36 transmits the feedbacksignal 40 to the second controller 18, and the second controller 18 maythen use the feedback signal 40 to update the stored data or programmingto refine the second controller's 18 ability to accurately predict thewind turbine generator's 12 response to the control signal 28.

If the predetermined threshold is met during the first cycle, thecomparator 36 sends a signal 42 to a switch 44 to change the operationof the first 16 and second 18 controllers for the second or subsequentcycle, as shown in FIG. 2. During the second or subsequent cycle, thesecond controller 18 receives the input signal 20 and the firstparameter signal 26 and generates the control signal 28 to the windturbine generator 12 based on the input signal 20 and the firstparameter signal 26. Similarly, during the second or subsequent cycle,the first controller 16 receives the first parameter signal 26 and thecontrol signal 28 (now from the second controller 18) and generates thepredicted parameter signal 30 based on the first parameter signal 26 andthe control signal 28. During the second cycle, the comparator 36transmits the feedback signal 38 to the first controller 16 if thepredetermined threshold is not met.

During operation, the system 10 uses one of the first 16 or second 18controllers to regulate the wind turbine generator 12, while the otherof the second 18 or first 16 controller receives feedback signals torefine the controller's ability to accurately predict the wind turbinegenerator's response to the control signal 28. For example, during thefirst cycle, the first controller 16 receives the input signal 20 andthe first parameter signal 26 and generates the control signal 28 to thewind turbine generator 12 to change the first parameter to equal theinput signal 20. Substantially simultaneously, the second controller 18receives the first parameter signal 26 and the control signal 28 fromthe first controller 16 and generates the predicted parameter signal 30that estimates the wind turbine generator's 12 response to the controlsignal 28 from the first controller 16. The delay circuit 32 producesthe second parameter signal 38 indexed to the output of the wind turbinegenerator 12 after the wind turbine generator 12 responds to the controlsignal 28. The feedback circuit 34 compares the predicted parametersignal 30 to the second parameter signal 38, and if the predeterminedthreshold (for example a time interval or a maximum difference betweenthe predicted parameter signal 30 and the second parameter signal 38) isnot met, then the comparator 36 transmits the feedback signal 40 back tothe second controller 18. The feedback signal 40 then updates the dataand/or programming stored in the second controller 18 to refine orimprove the ability of the second controller 18 to accurately predictthe wind turbine generator's 12 response to the control signal 28 (i.e.,reduce the difference between the predicted parameter signal 30 and thesecond parameter signal 38). The system 10 continues to operate insubsequent cycles with the first controller 16 regulating the windturbine generator 12 and the second controller 18 receiving additionalfeedback signals 40 until the predetermined threshold is met.

When the predetermined threshold is met, the comparator 36 sends asignal 42 to switch the operation of the first 16 and second 18controllers during subsequent cycles, as shown in FIG. 2. During thesecond or subsequent cycle, the second controller 18 now receives theinput signal 20 from the input device 14 and the first parameter signal26 from the wind turbine generator 12 and generates the control signal28 to the wind turbine generator 12. During the second or subsequentcycle, the first controller 16 receives the first parameter signal 26from the wind turbine generator 12 and the control signal 28 from thesecond controller 18 and generates the predicted parameter signal 30.The delay circuit 32 generates the second parameter signal 38, aspreviously discussed, and the feedback circuit 34 compares the secondparameter signal 38 to the predicted parameter signal 30 from the firstcontroller 16 to generate the feedback signal 40. During this second orsubsequent cycle, the comparator 36 transmits the feedback signal 40 tothe first controller 16 if the predetermined threshold is not met. Inthis manner, during the second or subsequent cycle, the secondcontroller 18 regulates the operation of the wind turbine generator 12,while the first controller 16 receives feedback signals 40 to refine orimprove the ability of the first controller 16 to accurately predict thewind turbine generator's 12 response to the control signal 38. When thepredetermined threshold is met during the second or subsequent cycle,the comparator 36 transmits the signal 42 to the switch 44, and thecommunication lines switch back to the configuration as shown in FIG. 1,and the process repeats.

FIGS. 3 and 4 show a system 50 for controlling a machine 52 according toan alternate embodiment of the present invention. The system 50 againincludes an input device 54 as previously discussed. In addition, thesystem 50 includes a controller 56, a first model 58, and a second model60. The controller 56, first model 58, and second model 60 may includeprocessors and/or memory/media elements, as previously discussed withrespect to the first 16 and second 18 controllers described andillustrated in FIGS. 1 and 2.

In the embodiment shown in FIGS. 3 and 4, the controller 56 receives aninput signal 62 from the input device 54 and a first parameter signal 64from the machine 52. The first parameter signal 64 conveys a measuredparameter of the machine 52, such as voltage or current, taken at afirst time. The controller 56 generates a request signal 66 that seeksinformation needed to generate a control signal 68 that will change thefirst parameter signal 64 to equal the input signal 62. For example, ifthe input signal 62 conveys a desired speed of 500 rpm and the firstparameter signal 64 conveys a measured speed of 450 rpm, the requestsignal 66 seeks information that can be used to generate the controlsignal 68 to change the actual speed from 450 rpm to 500 rpm.

During a first cycle, the first model 58 receives the request signal 66from the controller 56 and accesses the stored data and/or instructionsto generate a response signal 70. The response signal 70 conveysinformation to the controller 56 so the controller 56 can generate thecontrol signal 68 to change the output of the machine 52 to match thedesired operating parameter conveyed by the input signal 62.

Substantially simultaneously during this first cycle, the second model60 receives the first parameter signal 64 from the machine 52 and thecontrol signal 68 from the controller 56. The second model 60 accessesthe stored data and/or instructions to generate a predicted parametersignal 72 that estimates the machine's 52 response to the control signal68.

The system 50 includes a delay circuit 74, feedback circuit 76, andcomparator 78, as previously discussed with respect to the embodimentillustrated in FIGS. 1 and 2. The delay circuit 74 generates a secondparameter signal 84 indexed to a second time, and the second parametersignal 84 corresponds to the measured parameter after the machine 52 hasreceived and acted on the control signal 68. The feedback circuit 76compares the second parameter signal 84 to the predicted parametersignal 72 to generate a feedback signal 82. The comparator 78 transmitsthe feedback signal 82 to the second model 60 if a predeterminedthreshold is not met. The system 50 continues to operate duringsubsequent cycles with the first model 58 providing the response signal70 to the controller 56 and the second model 60 providing the predictedparameter signal 72 to the feedback circuit 76 until the predeterminedthreshold is met. When the predetermined threshold is met, thecomparator 78 sends a signal 84 to a switch 86 to change thecommunication lines between the system 50 components as shown in FIG. 4.

As shown in FIG. 4, during a second or subsequent cycle, the secondmodel 60 receives the request signal 66 from the controller 56 andgenerates the response signal 70 based on the request signal 66. Duringthe second or subsequent cycle, the first model 58 receives the firstparameter signal 64 from the machine 52 and the control signal 68 fromthe controller 56 and generates the predicted parameter signal 72.During the second or subsequent cycle, the comparator 78 transmits thefeedback signal 82 to the first model 58 if the predetermined thresholdis not met. In this manner, during the second or subsequent cycle, thecontroller 56 regulates the operating parameter of the machine 52 basedon information provided by the second model 60, while the first model 58receives feedback signals 82 to refine or improve the ability of thefirst model 58 to accurately predict the machine's response to thecontrol signal 68. As previously discussed with respect to theembodiment shown in FIGS. 1 and 2, the predetermined threshold may be atime interval, magnitude of the feedback signal, or other metricindicative of the ability of the first model 58 to accurately predictthe machine's response to the control signal 68.

FIGS. 5 and 6 show another embodiment of a system 90 for controlling amachine 92. The system 90 again includes an input device 94, controller96, first model 98, and second model 100, as previously discussed withrespect to the embodiment shown in FIGS. 3 and 4. In the embodimentshown in FIGS. 5 and 6, the first model 98 receives an input signal 102from the input device 94 and a first parameter signal 104 from themachine 92. The first model 98 accesses the stored data and/orinstructions to produce a response signal 106 based on the input signal102 and the first parameter signal 104. For example, if the input signal102 conveys a desired speed of 100 rpm and the first parameter signalconveys a measured speed of 110 rpm, the first model 98 generates aresponse signal 106 to the controller 96 that includes the informationnecessary for the controller 96 to generate an appropriate controlsignal 108 to change the operating speed of the machine from 110 rpm to100 rpm.

Substantially simultaneously during the first cycle, the second model100 receives the first parameter signal 104 from the machine and thecontrol signal 108 from the controller 96. The second model 100 accessesthe stored data and/or instructions to generate a predicted parametersignal 112 which represents the second model's 100 estimate of themachine's 92 response to the control signal 108.

The system again includes a delay circuit 114, feedback circuit 116, andcomparator 118 as previously described with respect to the embodimentsshown in FIGS. 1 through 4. The delay circuit 114 generates a secondparameter signal 120 indexed to a second time, and the second parametersignal 120 corresponds to the measured parameter after the machine 92has received and acted on the control signal 108. The feedback circuit116 compares the second parameter signal 120 to the predicted parametersignal 112 to generate a feedback signal 122. The comparator 118transmits the feedback signal 122 to the second model 100 if apredetermined threshold is not met. The feedback signal 122 refines thestored data and/or instructions in the second model 100 to allow thesecond model 100 to more accurately predict the machine's 92 response tothe control signal 108. The system 90 continues to operate duringsubsequent cycles with the first model 98 providing the response signal106 to the controller 96 and the second model 100 providing thepredicted parameter signal 112 to the feedback circuit 116 until thepredetermined threshold is met. When the predetermined threshold is met,the comparator 118 sends a signal 124 to a switch 126 to change thecommunication lines between the system 90 components as shown in FIG. 6.

As shown in FIG. 6, during the second or subsequent cycle, the secondmodel 100 receives the input signal 102 from the input device 94 and thefirst parameter signal 104 from the machine 92. The second model 100accesses the stored data and/or instructions to generate the responsesignal 106 based on the input signal 102 and the first parameter signal104. During the second or subsequent cycle, the first model 98 receivesthe first parameter signal 104 from the machine 92 and the controlsignal 108 from the controller 96. The first model 98 accesses thestored data and/or instructions to predict the response of the machine92 to the control signal 108 and generate the predicted parameter signal112. In this manner, the controller 96 regulates the operating parameterof the machine 92 based on information provided by the second model 100,while the first model 98 receives feedback signals 122 to improve theability of the first model 98 to accurately predict the machine'sresponse to the control signal 108. When the predetermined threshold ismet, the comparator 118 transmits the signal 124 to the switch 126, andthe communication lines between the controller 96, first model 98, andsecond model 100 change back as shown in FIG. 5.

As previously described, each embodiment of the present invention allowsa system to control an operating parameter of a machine whilesimultaneously updating a second or alternate controller or model. Inthis manner, the system can accurately regulate the operating parameterof the machine while simultaneously updating the second controller ormodel to reflect changes in the operation of the machine. As a result,the system is able to switch between a first controller and a secondcontroller or a first model and a second model so that the system canreliably remain updated to changes in the operating characteristics ofthe machine without requiring any interruption in the operation of themachine.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and may include other examplesthat occur to those skilled in the art. Such other examples are intendedto be within the scope of the claims if they include structural elementsthat do not differ from the literal language of the claims, or if theyinclude equivalent structural elements with insubstantial differencesfrom the literal languages of the claims.

1. A system for controlling a machine, comprising: a. an input signal,wherein the input signal conveys a desired operating parameter of themachine; b. a first parameter signal, wherein the first parameter signalconveys a measured parameter of the machine taken at a first time; c. afirst controller, wherein during a first cycle, the first controllerreceives the input signal and the first parameter signal and generates acontrol signal to the machine based on the input signal and the firstparameter signal; d. a second controller, wherein during the firstcycle, the second controller receives the first parameter signal and thecontrol signal and generates a predicted parameter signal based on thefirst parameter signal and the control signal; e. a second parametersignal, wherein the second parameter signal conveys the measuredparameter of the machine taken at a second time; f. a feedback circuit,wherein the feedback circuit receives the second parameter signal andthe predicted parameter signal and generates a feedback signal based onthe second parameter signal and the predicted parameter signal; and g. acomparator, wherein during the first cycle, the comparator receives thefeedback signal and transmits the feedback signal to the secondcontroller if a predetermined threshold is not met.
 2. The system ofclaim 1, wherein the comparator switches the first controller and thesecond controller if the predetermined threshold is met during the firstcycle, so that during a second cycle: a. the second controller receivesthe input signal and the first parameter signal and generates thecontrol signal to the machine based on the input signal and the firstparameter signal; b. the first controller receives the first parametersignal and the control signal and generates the predicted parametersignal based on the first parameter signal and the control signal; andc. the comparator transmits the feedback signal to the first controllerif the predetermined threshold is not met.
 3. The system of claim 2,wherein at least one of the first controller or the second controllerincludes programming that generates the predicted parameter signal. 4.The system of claim 3, wherein the feedback signal modifies theprogramming that generates the predicted parameter signal.
 5. The systemof claim 1, wherein the predetermined threshold is a time interval. 6.The system of claim 1, wherein the predetermined threshold is anacceptable magnitude for the feedback signal.
 7. A system forcontrolling a machine, comprising: a. an input signal, wherein the inputsignal conveys a desired operating parameter of the machine; b. a firstparameter signal, wherein the first parameter signal conveys a measuredparameter of the machine taken at a first time; c. a controller, whereinthe controller receives the input signal and the first parameter signaland generates a request signal based on the input signal and the firstparameter signal; d. a first model, wherein during a first cycle, thefirst model receives the request signal and generates a response signalbased on the request signal; e. wherein the controller receives theresponse signal and generates a control signal to the machine based onthe response signal; f. a second model, wherein during the first cycle,the second model receives the first parameter signal and the controlsignal and generates a predicted parameter signal based on the firstparameter signal and the control signal; g. a second parameter signal,wherein the second parameter signal conveys the measured parameter ofthe machine taken at a second time; h. a feedback circuit, wherein thefeedback circuit receives the second parameter signal and the predictedparameter signal and generates a feedback signal based on the secondparameter signal and the predicted parameter signal; and i. acomparator, wherein during the first cycle, the comparator receives thefeedback signal and transmits the feedback signal to the second model ifa predetermined threshold is not met.
 8. The system of claim 7, whereinthe comparator switches the first model and the second model if thepredetermined threshold is met during the first cycle, so that during asecond cycle: a. the second model receives the request signal andgenerates the response signal based on the request signal; b. the firstmodel receives the first parameter signal and the control signal andgenerates the predicted parameter signal based on the first parametersignal and the control signal; and c. the comparator transmits thefeedback signal to the first model if the predetermined threshold is notmet.
 9. The system of claim 8, wherein at least one of the first modelor the second model includes programming that generates the predictedparameter signal.
 10. The system of claim 9, wherein the feedback signalmodifies the programming that generates the predicted parameter signal.11. The system of claim 7, wherein the predetermined threshold is a timeinterval.
 12. The system of claim 7, wherein the predetermined thresholdis an acceptable magnitude for the feedback signal.
 13. The system ofclaim 7, wherein at least one of the first model or the second model islocated remotely from the controller.
 14. A method for controlling amachine, comprising: a. measuring a parameter at a first time todetermine a first parameter value; b. comparing the first parametervalue to a desired value; e. in a first cycle, transmitting a controlsignal from a first controller to the machine to vary the firstparameter value; d. measuring the parameter at a second time todetermine a second parameter value; e. in the first cycle, generating apredicted parameter value in a second controller based on the firstparameter value and the control signal; f. comparing the predictedparameter value to the second parameter value; g. generating a feedbacksignal based on the predicted parameter value and the second parametervalue; and h. in the first cycle, transmitting the feedback signal tothe second controller if a predetermined threshold is not met.
 15. Themethod of claim 14, further including modifying the second controllerbased on the feedback signal.
 16. The method of claim 14, furtherincluding switching the first controller and the second controller ifthe predetermined threshold is met during the first cycle, and furtherincluding during a second cycle: a. transmitting the control signal fromthe second controller to the machine; b. generating the predictedparameter value in the first controller based on the first parametervalue and the control signal; and c. transmitting the feedback signal tothe first controller if the predetermined threshold is not met.
 17. Themethod of claim 16, further including modifying the first controllerbased on the feedback signal.